The chucks on a new lathe are likely to be very tight until they've been on and off a few times. You should find they soon settle into a much more reasonable fit. No need for wedges or peripheral slots.

John's Rod in the chuck to waggle it is a good idea but be careful to waggle evenly so you don't wedge the chuck sideways on the register. (This makes the fit even tighter, and you may have done just that with your screwdriver.)

Also, with a suitable bit of wood between the chuck studding and the headstock, you can use the chuck's securing nuts to push the chuck off for 4 or 5mm. Once the chuck's moved a little John's rod should do the rest.

Dave

I would suggest that threaded holes in the mandrel would be the ideal means of jacking the chuck off. It should be a tight fit to maintain concentricity. The faceplate should be machined as a tight fit as well.

A better alternative is the bar in the chuck jaws and use it as a slide hammer, to pull the chuck off square (think here a suitable bolt, with nut, and a lump of suitable metal bored to slide on the bolt).

Also, best to refit your chuck(s) in the same position every time they are replaced, particularly for a self centering chuck, or a different concentrity error may be apparent on replacement.

I find it quicker to change chucks than to change from inside to outside jaws

Norman,

Are you still using the Loughborough? I little different than a chuck bolted on the spindle. So much quicker to change chucks with a theaded spindle, but the bolted on type can be used, under power, in both directions, unlike the threaded spindle lathes.

Brilliant!

Yep, brill idea, as long as everyone can accomodate their machine with sufficient space behind the spindle. I'm currently repositioning my lathe to leave space for longer bars of stock to protrude rearwards. There is always the exception that defeats the rule!

Edited to add that I like Joe Pie's wooden chuck support blocks (u-toob) where he just slides the chuck along on the appropriate block and it mates/aligns almost perfectly with the spindle.

Edited By not done it yet on 26/10/2017 21:33:20

just drill a hole in the wall. you can always put a plug in it when it is not needed.

Again the exception? My lathe is not positioned against a wall. The item immediately behind the lathe it is not a suitable candidate for having holes drilled through it (nor easily moved).

If all else fails you can always ease the mating surfaces with a bit of emery paper to make them a neat sliding fit rather than an interference fit.

Or if you havent got room to use the mentioned long bar and big 'ammer through the chuck, you could grip a large nut in the chuck and tighten a large bolt down against the end of the spindle, protected by suitable plug of brass etc, and ease the chuck off that way. Half inch diameter UNF or similar nut and bolt would do the job.

Edited By Hopper on 27/10/2017 08:26:18

Use a slide hammer version of Jason's tip

Clearly not read my post before Jason's, where I suggested the slide hammer? (@16:36:35).

All this hammering doesn't sound like the best treatment of the bearings. Until it eases off do make sure you aren't trying to take it off after a bit of running has warmed up the bearings and hence the mandrel but the chuck is still cold. Also don't put a hot chuck on a cold nose.

It looks like the chuck bolts are actually studs that go through to the back of the mandrel nose plate with nuts at the back. Same as my Hobbymat.
Make a spacer that fits between the back of a stud and the front of the headstock with 1/2mm clearance then as you undo the nut it will hit this spacer. Half a turn with the spanner will jack the chuck forward. Then move round to the next stud etc and you have effectively built in jacking points. No impact stress on the bearings.

You can also make a card washer (postcard or birthday card) to fit between the chuck and nose plate. Actually 3 slips of card is all that is needed. This will form a gap that may help avoid the very tightest part and forms a slot if you still resort to the screwdriver.

After thinking about it the best thing would be to make some special long nuts or get some coupling nuts and cut to length.